Is orange peel new superfuel?

A BRITISH scientist has discovered a revolutionary way to turn orange peel into oil – by using a microwave.

Professor James Clark has discovered a revolutionary way to turn orange peel into oil []

Professor James Clark found high-powered microwaves could break down the molecules in fruit peel to release gases that could be collected and distilled into a liquid product.

These valuable gases were then used to produce oil, plastics, chemicals and fuels. Among them was pectin, a thickening agent in jam, which was turned into motor fuel and also carbon used in water purifying machines. Limonene, the chemical that gives citrus fruits their distinctive smell, was used in cosmetics and cleaning products, as well as glue.

Professor Clark claims the microwave method could also be used on a variety of plant-based waste to make fuel or other products. They include straw, cashew nut shells, apple peel, coffee or rice husks.

He said: “Waste orange peel is an excellent example of a wasted resource. In Brazil, the world’s largest producer of orange juice, half the orange fruit is left as waste once the juice has been recovered. This corresponds to eight million tons a year of orange peel that can be used to produce chemicals, materials and fuels.”

Professor James Clark has discovered a revolutionary way to turn orange peel into oil

He built the £200,000 microwave, which looks like one found in any kitchen, at his laboratory in the Green Chemistry Centre at the University of York. It can only treat small amounts of food waste, but by December a model that can process 30 kilos of waste an hour is due to be in operation.

And Prof Clark says much bigger models, costing £1million, could treat six tons of food waste an hour and could soon become a familiar sight at recycling centres across the country. They could also be sited at shopping centres to treat waste food from cafes and restaurants.

“The unique feature of our microwave is that we work at deliberately low temperatures. We never go above 200C,” Prof Clark said. “You can take the limonene off or you can turn limonene into other chemicals. It works really well with waste paper. It can take a big range of bio-waste material.”

York University has now set up OPEC, the Orange Peel Exploitation Company, backed by investors from Brazil and Spain to further test how to make the most of the mountains of waste left over from the fruit juice industry.

Prof Clark also believes his microwave discovery could benefit power stations by doubling the energy they produce.

He said: “We’re talking to power stations about materials that they are already bringing in for microwaving as well.

“If you put typical waste into our system before you burn it, the calorific value doubles compared to what it was before.”

Meanwhile, a conservation group has set a new land speed record for a car fuelled by leftover coffee. A modified 1974 Rover, nicknamed the Carpaccino, reached 75mph at the Elvington Race Track near York last Wednesday.

The Teesdale Conservation Volunteers group, which built the car, used 10 kilos of waste coffee grounds, which were turned into pellets then burned to produce a flammable gas. It provided enough fuel for the car to travel 100 miles. Spokesman Martin Bacon said: “Cars don’t have to just run on fuels that are dug out of the ground.”